ST. LOUIS — The ruins were everywhere on Sunday. The evidence was overwhelming.

The crumbling equation was right there: Colin Kaepernick + the 49ers’ offensive game plan + Jim Tomsula + Trent Baalke + Jed York = a lost and broken franchise.

There’s no way for the 49ers to escape the reality now — and whenever the 49ers tried that Sunday, the Rams literally knocked them backward.

Back to 2004 or 2010 and the bad old days. When they were bad and knew they were bad.

“When I signed up, I signed up to play through wins, losses or whatever,” linebacker NaVorro Bowman said after the 49ers’ 27-6 loss in St. Louis. “This is the type of team we have. There’s no genie that’s coming through the door.”

The 49ers were in the Super Bowl three seasons ago, in the NFC Championship game two seasons ago, and now …

They’re searching for something they threw away and can’t get back, and opponents are proving this every week.

The 49ers probably don’t have the right coach, quarterback or offensive coordinator, their general manager has been on a bad personnel streak and their owner is a ghost.

They’re lost. And nothing underlines that more than having zero chance against the mediocre Rams — who outgained the 49ers 388-189 — because the 49ers’ offense has zero chance against anybody who plays decent defense.

Aren’t they trying different things on offense? What in the world are the 49ers doing?

“Obviously I haven’t gotten to the right answer yet,” Tomsula said afterward. “But we’ll find the right answer.”

Could they start to consider benching Kaepernick — who was 20 for 41 for 162 yards — in favor of backup Blaine Gabbert?

“I’m not going to get into all that today,” Tomsula said. “I’ll get into that after we’ve had the opportunity to watch the tape.”

That was not exactly a soaring commitment to Kaepernick.

Nor should Tomsula be committed to Kaepernick after this run of terrible offense and scattered QB play, including a play in the first quarter when the QB didn’t see that receiver Torrey Smith was left uncovered because the Rams knew Kaepernick wasn’t going to throw backed up on his own goal line.

A few plays later: 49ers tailback Mike Davis was tackled in the end zone for a safety.

So yes, the QB play is way, way below acceptable.

Would Kaepernick understand if the 49ers think about benching him?

“To me, I’m doing everything I can to win games,” Kaepernick said.

“Whether they make that change or not is their decision. But I’ll give this team everything I have every week.”

But Tomsula isn’t qualified to make that call, offensive coordinator Geep Chryst certainly hasn’t made things any easier, and why would anybody think Gabbert could do any better with that coach, that offensive coordinator and the woeful offensive line Baalke put together?

When any one of these positions is wrong, it can screw up a franchise.

The 49ers’ great 2015 accomplishment is that they’ve gotten each part of this so badly, terribly, ruinously wrong.

Gabbert isn’t the answer, not really, and the idea of him behind the 49ers’ offensive line probably scares even him.

Getting rid of Baalke and letting York try to find another credible GM probably isn’t the answer because York bet it all on Baalke when the two men fired Jim Harbaugh last December.

Now they don’t even have a quick way to eject themselves from any of these decisions, because each wrong piece is interlocked with the others.

And each wrong piece is weighed down by all the other wrong pieces.

You saw it in Tomsula’s drooped posture, every one of Kaepernick’s misfired passes and each time Chryst chose to run the ball in a passing situation simply because he didn’t trust Kaepernick to throw.

You heard it in the players’ quiet, resigned voices afterward, and you felt it all throughout this dud.

“You can only control individually what you do on the field, what your performance is,” left tackle Joe Staley said.

“You can’t worry about what anybody else is doing out there. You’ve got to control what you can control on the football field.”

On Sunday, the 49ers defense was fine. Not great — the 49ers gave up a 71-yard touchdown run to Todd Gurley and a few other big plays, but at some point any defense is going to break when its offense can’t move the ball.

“I can’t comment on the offense, man,” Bowman said, before adding:

“I wish I could just go ask the coach to play running back, or something. But that’s not how this business works.”

This is the business: The 49ers are 2-6, their offense is easily the league’s worst, they’ve been crushed by all three of their division rivals already, and they have deleted themselves from NFL contention and relevancy.

It took seven games in 2015 to do that — and about a hundred big and medium-sized terrible decisions, all adding up to so much ruin.